Sliding-barrel rotary-cutter-spindle cutter head



5 Sheets-Sheet l l lh/manto@ Aug. 22, 1933. G. GoR'roN SLIDING BARREL ROTARY CUTTER SPINDLE CUTTER HEAD Filed April 10, 1931 jr 4. s f 6 s i ssrh 1 ldl 5 MA LH 2 8 G. GoRToN 1,923,820 Y SLIDING BARREL ROTARY CUTTER SPINDLE CUTTER HEAD Aug. 22, 1933.

Filed`April l0, 1931 5 Sheets-Sheet 2 Aug. 22, 1933. G. GoRToN 1,923,820

SLIDING BARREL ROTARY CUTTER SPINDLE CUTTER HEAD FileCLApril l0. 1931 3 SheecS-Sheel'l 3' Patented Aug. 22, 1933 SLIDING-BARREL ROTARY-CUTTER-SPIN- DLE CUTTER HEAD George Gorton, Racine, Wis.

Application April 10, 1931. Serial No. 529,157

9 Claims.

This invention relates to a cutter head assembly for routing and other machine tools and the like wherein the rotary cutter spindle is mounted in and is carried to and from and held to the work by a sliding barrel; and the objects and nature of the invention will be understood by those skilled in the art in the light oi the following explanations of the accompanying drawings that show what I now believe to be the preferred mechanical expressions or embodiments of my invention from among other constructions, arrangements and combinations within the spirit and scope thereof.

In tools that embody longitudinally slide-ble non-rotary barrels that carry the rotary cutter spindles mounted therein against substantial or objectionable relative or independent lateral and longitudinal movements with the spindles projecting or depending longitudinally from the barrels to hold and actuate the longitudinally projecting rotary cutters, serious loss of time and expense is involved in maintaining the bearing, particularly the lower end bearing 01"' the barrel in the cutter head, against such looseness as 5 causes objectionable lateral play or movement of the rotary cutter. The lateral pressures and stresses of the cutter at work, are transmitted to the slidable barrel usually causing increased lateral pressure of the barrel against its bearing surfaces, with resulting wear and increasing lateral looseness and poor and inefhcient cutter work and lack of accuracy.

Barrels have usually been mounted at one or both ends in bearings each having an adjustable cap as per the construction of such bearings where the cap consists of one-half of the bearing, and when looseness developed such looseness was taken up so far as possible, by removing a portion oi the material on the ilat surfaces of the cap wl ch iits against one-half of the bearing thus allowing the cap to close somewhat on the barrel. When adjustment is made in this manner the bea-ri surface is closed in one direction. lt would of course be worn large in every direction but a bearing so closed would be still large laterally and even after adjusted would not leave a true cylindrical bearing clear arounc the bearing surface hence it would again become loose much sooner than if it had a perfect bearing entirely around. To adjust or close up a bearing ci this natu quires more or less skill and consderable ne and even when done by skillful men is never a perfect job for the reason given above and tl ereiore not altogether satisfactory.

An object oi the invention is to provide simple, comparatively-inexpensive, easily and quickly operated., and durable means for overcoming the hereinbeiore mentioned problem, with the ends in view of increasing the working efficiency and accuracy, and decreasing the cost of maintaining tools that embody rotary cutter spindles carried slidable barrels.

A iurther object of the invention is to pro-l yice improved means whereby the bearing in a cutter head for the sliding barrel that carries the rotary cutter spindle oi a machine or other tool, can be quickly adjusted from time to time,

iter the original installation and fitting, to take up subsequent lateral looseness oi the barrel due to wear or other causes.

With the foregoing, and other objects in View my invention consists in certain novel features in structure, iormation or combination, as more fully and particularly hereinafter explained and specined.

Referring to the accompanying drawings, forming part hereof Fig. l is a side elevation of a cutter head assembly embodying my invention, the cutter head being broken away.

Fig. 2 shows the cutter head of Fig. 1 in side elevation turned 90 from the position of Fig. 1.

Fig. 3 is a vertical longitudinal section on the line 3 3, Fig. l.

Fig. i is a cross section on the line 4 4, Fig. 1.

Fig. 5 is a cross section on the line 5 5, Fig. 1.

Fig. 6 is a vertical section on the line 6 6, Fig. 7, showing a different species or form oi my invention.

'I shows the construction oi Fig. 6 in bottom plan or end elevation. Y

Fig. 8 is a vertical longitudinal section onthe line 8 8, Fig. 9, showing another species or modification oi my invention.

Fig. 9 shows the structure of Fig. 8 in bottom plan or elevation.

Fig. l() is a longitudinal section on the line l0 1, Fig. 11, showing my invention in still a different modied form or species.

l1 shows the construction o1 Fig. 10 in bottom plan or end elevation.

The cutter heads disclosed are more or less typical or those employed in various machine and other tools, and merely as an example, reference is made to the machine tool disclosed by my pending application led August 21, 1929, Serial No. 387,330 (of which this application is in part a continuation) for complete disclosure of a machine tool example, from among others, its cutter head, its sliding barrel, means for counter-balancing the barrel and its load, means for feeding and controlling the barrel, a rotary cutter spindle mounted in and carried by the barrel and its drive and cutter chuck or collet, etc.

In Figs. 1 5, the cutter head housing 1, is, at least at its lower end portion, longitudinally split or slotted, see 2, to provide a contractile split clamp. In the constructions of Figs.v 6 11, the cutter head housings la, shown are of the non-split or non-clamp forming type.

In all of the forms illustrated, I show non-rotary usually-cylindrical rotary cutter spindle carrying barrel or slide 3, mounted and longitudinally slidable in its cutter head housing and at its lower end depending therefrom. These barrels are of any suitable formation and construction, and any suitable means are provided for moving said barrels longitudinally in their respective cutter head housings and for holding them at the desired elevations, as appears, for example, in the disclosure of my said parent application.

In the various constructions illustrated, each slidable barrel 3, carries a rotary cutter spindle 4, of any suitable formation or construction, at its depending lower end equipped to receive, hold and drive a preferably renewable rotary cutter 5, in longitudinal downward continuation of the spindle. Usually, the downwardly projecting end of the rotary spindle 4, carries a suitable chuck or collet for removably clamping the cutter 5. For-instance, I show a collet 6, which is provided With suitable actuating means, for instance, such as illustrated by my said parent application.

rIhe rotary cutter spindle is, in the example shown, concentrically arranged within the barrel 3, and projects downwardly therefrom and is mounted therein, usually by thrust bearings 7, against objectional relative lateral and longitudinal movements. Any suitable driving means (not shown) is provided for the cutter spindle; an example of a suitable drive is illustrated by my said parent application.

In the operation of the cutter on the work, the cutter is subjected to lateral stresses and pressures, and this is particularly true of routing and milling operations, and these lateral pressures and stresses are in an exaggerated manner transmitted to the slidable barrel in which the cutter is mounted, and this is particularly true of the lower end portion of the barrel, and hence lthe lower bearing for the barrel in the lower end or lower portion of the cutter head housing receives these stresses and pressures and is thereby subjected to more or less excessive wear, yet to attain efficient and accurate cutter operation, this lower end barrel bearing must be constantly maintained tight and snug to prevent objectionable lateral looseness and play of the barrel which play and looseness willV be exaggerated at the working point of the cutter. -Y This lower end bearing must also have running sliding fit with the barrel to permit the desired more or less free sliding movement of the barrel in the cutter head housing, the requirements being that the `barrel be mounted in the cutter head housing, for example approximately as disclosed by my said parent application, with a running sliding iit while held against rotation and maintained against such objectionable lateral play as will be transmitted to the rotary cutter, even though the instant case shows but the guiding bearing between the lower end portions of the barrel and cutter head housing.

My invention involves the provision of comparatively simple guiding bearing means to hold the lower portion of the barrel against objectionable lateral play while providing the desired running sliding t between the same and the cutter head housing, of such peculiar characteristics as to be capable by a comparatively easy quick operation, in situ, of taking up wear and lateral looseness from time to time during the months and possibly years of tool operation, to maintain through a long period of operation without bearing renewal, the maximum accuracy of cutter operation by reduction of cutter lateral play or looseness to the minimum.

I employ a non-split or unbroken ring, annulus, sleeve or bushing of suitable hard material, such as hardened steel or alloy, to form the accurately tted guiding bearing for, preferably, the lower end portion ci the cutter spindle barrel, so that when the barrel, its complementary bearing bushing, and cutter head housing are originally assembled, the barrel will be tight against objectionable lateral looseness and will t within the bushing with a running' sliding rit to permit barrel reciprocation, and I also provide any suitable holding or clamping means for xedly holding or clamping said bushing to and in operative position in and with respect to the cutter head housing, such means providing for bushing removal and renewal; and I successfully solved the hereinbefore identified machine tool problem, by providing a bearing bushing that is resilient or compressible and characterized by capacity of progressively or repeatedly contracting in diameter step by step from its original diameter to the minimum diameter within compressiblo capacity, under periodical application of the necessary exteriorly applied bushing-compressing force or pressure; and by combining with the cutter head housing and such peculiar guiding bearing bushing, holding or clamping means characterized by its capacity of not only ilxedly leiding the unworn new bushing in the barrelhousing assembly, but. also possessing the reserve capacity for periodically :from time to time compressing said bushing in situ, as barrel looseness develops by wear to progressively and repeatedly contract the same in diameter step by step while maintaining its approximate cylindrical form, as required by wear, over a long period of machine operation, and to still ixedly hold the bushing after each contraction, in operative position in the assembly.

In the form of Figs. 1-5, the cylindrical barrel guiding bearing bushing 8, is snugly itted within the lower end of the cutter head housing l, and surrounds the cylindrical lower end of the slidable barrel 3, with a running sliding fit and iits such barrel when new with such snugness as to prevent objectionable lateral looseness or play. The split lower end of the housing is equipped with clamping screw 9, to provide a clamp that can expand to admit the bushing during assembly of the barrel and bushing, and then contract to merely clamp the bushing iixedly in operative position. This clamp also functions to permit bushing removal and renewal.

The bushing 8, in addition to its mere guidimr and bearing function, also as hereinbefore set forth, is resilient or radially and annularly compressible and capable of contracting from its original diameter to permit progressive reduction in its diameter by repeated steps within its compressible limit.

The split clamp of the housing, is also construed and designed to provide the same with a reserve capacity for applying the necessary inward radial compressing force to,l step by step, as required by wear, compress and contract said bushing to the reduced diameter and later to the still further reduced diameter 'necessary at each compression to take up the then existing looseness. and to thus hold the bushing after each compression.

The cooperating or contacting surfaces of the bushing the barrel are accurately dimensioned and llnished and preferably hardened, if so desired can be glass hard. The bushing is relatively quite thin radially with respect to its di ameter, and these bushings are usually several inches in over all diameter.

The clamp formed by the split portion oi housing l, and the connecting bolt or screw, is designed to radially compress cylindrical bushing 8, inwardly toward the longitudinal axis thereof while maintaining the cylindrical form of the bushing at each reduced diameter to which contracted, and while maintaining the cylindrical form of the interior of the clamp throughout its range of contraction, with the end in view of avoiding the reduction of the bushing to an elliptical form in cross section during contraction.

In the construction of Figs. 1--5, the split end of the housing l, is peculiarly iornied to prevent the walls at opposite sides of the slot 2, from being drawn inwardly beyond the inner circle of the housing, by the contracting screw.

The cross sections Figs. e and 5, show that the split clamp is weakened diametrically opposite slot 2, and increased in thickness at each side of said slot, with elongated eyes or lugs 10., to receive the powerful elongated clamping screw 9, and its complementary screw threads in one of said eyes, with the slot 2, of increased width when the clamp is fixedly holding a new unworn bushing 8.

The purpose of the formation is to maintain the round or cylindrical form of the interior of the clamp throughout its contracting range to preserve at all times the cylindrical form of the inner surface of the bushing 8.

The bushing, in all forms shown, is composed oi such hardened material and of such diameter and radial thickness as to have a reserve capacity for repeated compressions or contractions.

Usually, where my invention is employed with hardened barrels, and the hardened bushing is contracted in situ -from time to time as barrel looseness develops, the bushing will last for a long time, say a year or longer, before the bushing has iinally reached its minimum contracting capacity and bushing renewal becomes desirable.

Usually, when barrel looseness develops from wear, bushing diameter contraction of say about one hah" o one thousandths of an inch is suicient to tighten the barrel against objectionable shake or looseness, where the machine is closely watched and regularly inspected for and promptly tightened to take up barrel looseness. When objectionable looseness again develops, a further bushing diameter contraction of, say, about the saine fraction of an inch, will usually produce the desired barrel tightness, and so on, until the total contraction from the original bushing diameter brings the bushing to its limit of contracting capacity. In the specific errar--- ple just recited where the progressive repeated bushing contractions each reduce the bushing diameter about one half of one thousandths of an inch more or less, the total contracting capacity rom the original diameter of the particular bushing of this example when new, will be about wo one thousandths of an inch, more or less, al though I do not wish to so limit my invention.

In the form of my invention illustrated by Figs. 6 and '7, I show a non-split or un roken cutter head housing in the bore of which the non-rotary barrel 3, is fitted and longitudinally reciprocatory. This barrel carries the rotary cutter spindie e, as hereinbeiore set forth. The lower end of the hardened barrel 3, is surrounded by and passes through the hardened compressible guiding bearing bushing, ring or annulus 8, with aV running slidable it and is thereby held against objectionable lateral play, as hereinbefore de scribed, and the bushing 8, posseses the characteristics of the bushing 8, of Figs. 1 5.

In Figs. 6 7, the cylindrical bushing 8, is iixedly, yet removably, held in the lower end of the cutter head 1c, in operative relation to the barrel 3, by a longitudinally-split resilient contractile conical wedge or cone 10, having a central longi- I tudinal cylindrical bore in which the bushing 8, is longitudinally, yet removably, arranged. The lower end o'l this bushing-holding and contracting conical wedge extends below the level. of the lower end of head 1c, and is formed with an eX- terior annular outwardly projecting i'iange 10c, having a circular series of slots 10b, to receive headed vertical clamping and forcing bolts l1, de pending from head la, through said slots with their wrench receiving heads abutting the under side of ila-nge 10a. The head la, is formed with a circular series of longitudinally elongated vertical internally screw threaded sockets lc, in which the bolts l1, respectively, are longitudinally adjustable by rotation, with the bolt screw threads meshing with the socket screw threads to anchor the bolts to head la, to raise the bolt heads and consequently the cone wedge 1G, with respect to head la, by rotation of the bolts in the proper direction and to hold the cone wedge in the position to which elevated.

The cone wedge exteriorly reduces from the flange loa, upwardly to its upper endv by a grad ual conical taper 10c, and the lower end ci the bore of head la, is enlarged downwardly by a corresponding downwardly haring longitudinal'taper to provide upwardly contracting conical surface id, against which the downwardly enlarging exterior longitudinal conical. surface 10c, fits and by which it is backed.

These conica-l slide surfaces 1d, 10c, are lso formed and arranged. that when the conical wedg 10, is forced upwardly within the head la, by successive rotation the screws 11, the conical wedge will be gradually contracted thereby gradually decreasing the diameter of its bore to annularly and radially compress and contract the bushing 8, tightly located in said bore and thereby reduce the bushing diameter while maintaining the cylindrical form thereof, to the extent necessary to produce the desired snug running sliding nt between the barrel 3, and the inner surface 01 the bushing.

The enlarged lower end of the bore of head la, is of sufficient length vertically and extends a suicient distance upwardly beyond the level oi the upper ends of bushing 8, and conical wedge 10, when these parts are in their original positions as rst assembled with an unworn bushing held by said wedge snugly fitting the barrel and holding the same against objectionable lateral play or shaking, to permit the progressive repeated upward bushing contracting steps or movements, of the bushing and conical wedge together, to progressively contract the bushing on the barrel as necessitated by wear, to the full compressing capacity of 'the bushing, whereupon renewal thereof is desirable.

In the constructions illustrated by Figs. 8-l1, I also show the nonsplit or unbroken cutter head housing la, having the lower end of its bore formed to provide a downwardly flaring or enlarging taper to provide upwardly contracting conical or wedge slide surfaces to cooperate with upwardly contracting conical or wedge slide surfaces carried by o1' moving with the contractile bushing, with screw threaded connecting or controlling means, all to cooperate to attain the results hereinbeiore explained. In these last mentioned drawing figures, the contractile resilient compressiole bushings 3c, possessing the characteristics of the bushings 8, hereinheiore described, are formed or otherwise provided as a iXed perinanent part thereof with a circular series or" longitudinal spaced exterior wedges 8d, the exterior circle of which constitutes upwardly contracting conical wedge to cooperate on relative up ward movement ,'itli the complementary upwardly contracting conical wer ge s race of head bore, in compressing contracting the bushing around the barrel 3, while constantly maintaining the cylindrical form or 'the inner surface or said bushing.

In the constru tion of 8--9, the conical slide surrace lg, of the ocre of head la, can be in part formed cy an inserted hardened rii d lll, although I do not wish to .N liinit ir y'enon The bushing is forced upw- "ily from time to ti to cause progressive contrae the bushing., as hereinheore explained, an ld l. each eleration to ich thus l llc, having their wi nch receiving heads' below and 'upwardly abutting cottoin e d face ci" the bushing, with bolts located in 'tlie s` between the radial exterior wedges tending therefrom un. t f into tlie elo vertical scrfY 'threaded sockets la, and meshing with the sci-en The operation is obvious threads tliereor. the light oi the foregoing. The bu" ings in this structure are also obviously removable and renovable, as Well in the structure or" gs. lllll In the structure .lc-V the soaced loncitudinal radially proiecting elVA rior v1ges 8d, id with the contract bushing 8c, at their upwardly convegingaces directly e: and slide upwardly on the upwardly contracting conical surface lj, oi the 3c, is to nut l5, having spanzn to function in ing on the be wt iorth while maintaining tine cylindrical forni ci' f" here oi head la, when the ring bushing. The lower end of the bore of f1/5 is cylindrical, relatively enlarged, a

threaded, lh, below the removable to receive and mesh with ieinoinanlc ring nut l5, at its top face bea i l A lower end of the contractile hashing Se, to

' ce the saine upwardly for progres-- ive contraction and to hold the same at the vation to which force It is evident that various changes, d additions, and rnod ig to without departing from. the of my invention siA following claiin the prior art elle..

viv

to deter-reine i the cto, and hence the foregoing presented as explanatory and not as limicept where so required by t le priorart.

What I claim is:- l. .ln a machine tool cutter-headasseinely sup c, nous lower end forming a progressively contractile roeaseo split ring clamp having a cylindrical bore maintained throughout its contraction; a barrel longitudinally arranged in said housing; a rotary cut spindle mounted in and carried by said barrel; and a radially contractile nonsplit be( ng and guide bushing having a capacity repeated ha 'el tightening compressions constantly maintaining cylindrical forni, slidab'l surrounding the lower end within and 'neld oy said clame and adapted to he co by the clainp to contract bushing to accurately engage tlie oarr l with a sliding ilt.

2. En a machine tool cutter head assembly; a non-rotary lo `gitudinally slidable barrel provided i th a rotary cutter soir tractilc oeaiil 1 said housing and clamp and provided with a @tary cutter spindle rod by the Teara radially conical ocre O4uide f bearing bushin said olaf-n surrounding said barrel and adapted to ne progressively and reneatedly contracted by said clainp to repeatedly duce the cylindrical bore of the bushing to 1e as required noly having g a sliding h ,l rot ry cutte :,rrel, a non-split Y for and surrounding -fl 'barrel and and means eX- ushing for normally ng and lor exterior-ly Ysing pressure on the saine and progressively it bore 'while maintainV- .cci'coi, said fneans in ,d screw threaded presu ein,

lon Cfi he 'oai and repeatedly ret-. time to 'time bly applying said inward compressing pressure to oarrel longitudinally arranged and l said shaking or nieans embodying an unbroken nornially compr o icle gui ng bushing ing a cylindrical `ocre receiving said barrel, said buslin" characterized ey reserve capacity of "ally two oneusandths ci an inch for progressive repeated contractinO4 to reduce its here diaineter i'roin tiine to time as looseness develops oy wear while maintaining its cylindrical foi-rn, and bushing holding and contracting ineans having the reserve capacity of repeatedly applying inward radial compressing pressure on said bushing to progressively reduce its bore diameter step 'oy step and to thus hold the bushing after each contraction.

7. A cutter head assembly that includes a cutter head housing; a rotary cutter spindle' is for holding and inoving the cutter to and troni the work; a non-split radially coinpressible guiding bearing bushing for maintaining the spindle against excessive looseness; and ineans `lor fixedly holding and progressively compressing said bushing to contract the saine sten by step ernloodying an annular longitudinally Allaring surface normally rigid. with said housing, said bushing having means movable longitudinally therewith and slidably contacting said surface to cooperate therewith in holding and contracting the bushing on relative longitudinal movement between the bushing and surface; and screw threaded means ior for lng the bushing longitudinally with respect to surface.

ln combination, a cutter head housing havecre providing an annular longitudinal ilaring taper; a sliding barrel arranged in said bore; y cutter spindle carried oy said barrel; a compr Eole guiding bearing bushing surroundshf 'Darrel to hold the same and the spindle excessive lat al play; a contractile cone f'flitly surrounding said bushing and tted daring taper to be contracted thereby to coxipress and contract the bushing by relative itudinal movement oi' the wedge and bushing said taper; and screw means for forcing the cone wedge longitudinally of said taper.

e. in combination, a cutter head housing having within its bore a normally-fixed annular longitudinal flaring tapered surface; a barrel slidaole longitudinally in the bore of said housing and carrying a rotary cutter spindle; a radially compressible guiding bearing bushing having a cylindrical bore snugly receiving said barrel and contractile to progressively reduce its bore diameter, said bushing having exterior slide surfaces engaging said tap-ered surface to cooperate therewith in progressively contracting said bushing as the bushing is forced longitudinally of said ia aered surface; and a screw threaded connection -oetween the bushing and cutter head for thus forcing the bushing longitudinally.

GEORGE GORTON. 

